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Snot and Mucus Decoded: The Meaning of Snot Colors

Candace has a broad range of interests that keep her head filled with strange facts, such as experimental cooking, games, and mad science.

Ever wondered what the color of your mucus means?

Ever wondered what the color of your mucus means?

Booger, mucus, runny nose—whatever you call it, it is still gross. But did you know the color of your snot can tell you a lot about what is going on inside your body?

Excess mucus can be caused by allergies, viral infections, and bacterial infections, and the colors can vary wildly with all of these conditions as well.

What does your snot say about you?

Do you know what boogers are?

Boogers are made of dirt and dust that has gotten stuck inside your nose. The mucus covers it, and it eventually dries up.

This article will go into more detail about the different colors of snot and what they can mean; but first, a few commonly asked questions:

What Does Bright Yellow Snot Mean?

Though the color of your snot is by no means a definitive way to diagnose an illness, bright yellow snot generally indicates that your body is fighting off an infection of some kind. At the beginning of a cold (which usually lasts 10 - 14 days), the snot may be the brightest, possibly turning green or darker yellow after that.

Green vs. Yellow Snot

You can have an infection and not have green snot, or you could not have an infection and have green snot. There is no direct correlation between the type of infection and the color of snot, though the color of your snot may give some indication as to the length of your infection.1

What About Orange Snot?

Very yellow or golden snot can sometimes look orange, and sometimes a little blood mixed in with the yellow snot can also cause it to have an orange-y appearance.

Snot Color Meaning Chart

Color CauseTreatment

Clear

This is normal, though excess clear mucus could indicate allergies

If caused by allergies, take antihistamines.

White

Dairy consumption or congestion

Usually resolves itself

Yellow

Your body fighting off a virus or cold

See your doctor if it lasts more than a week or you develop a fever.

Green

Viral, bacterial, or fungal infection

See your doctor if it lasts more than a week or you develop a fever.

Blue

The bacteria Pseudomonas pyocyanea

See your doctor if it lasts several days.

Orange, red, or reddish-brown

Blood

See your doctor if it lasts several days or if there is a lot of blood

Brown

Smoking

Smoke less.

Black or gray

Dirt, dust, or pollution

Stay indoors when pollution is bad.

What Is Mucus, Anyway?

It lines the nose as well as other organs,2 acting as a guard against bad stuff that might enter the body, such as dirt and germs. It is made of water, cells, salts, and mucin, which is a glycoprotein.

It goes by different names depending on its location in the body. Here are some terms you may hear, all referring to mucus found in the upper respiratory system:

  • Snot—the stuff coming from the nose.
  • Phlegm—the stuff in your throat and anything that you might cough up.
  • Sputum—a coughed-up mixture of mucus and saliva.
  • Postnasal drip—the stuff that flows from the nasal cavity down the throat.

Mucus Decoded: In Depth

Its color and texture can indicate what is going on in the body and can be signs of a virus, infection, or other problem. Read below to find out what the color of your mucus may mean.

Clear

Clear mucus with the consistency of glue is normal, although excessive amounts could be due to allergies.

Clear mucus with the consistency of glue is normal, although excessive amounts could be due to allergies.

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Read More From Youmemindbody

Normal mucus is a clear color and is thick and viscous, similar to the texture of glue. You probably don’t have any infection or virus if your snot is clear.2 As long as your body isn’t producing too much or too little of it, and as long it is the right texture, you should be in good health.

If your body is producing an excess amount, the likely cause is allergies. Talk to your doctor about appropriate treatment.

White

Dairy does not cause your body to produce more phlegm, though it does cause the mucus already in your body to thicken.

Dairy does not cause your body to produce more phlegm, though it does cause the mucus already in your body to thicken.

If your snot is white, it usually means that you're congested.3 According to Cleveland Clinic, this can happen when your mucus loses moisture and is flowing more slowly due to the inflammation in your nostrils. The presence of white mucus alone is no cause for alarm and is considered normal. You could be congested for a number of reasons. Drinking milk can also cause your phlegm to thicken, thus turning it white.4

Though it might thicken your phlegm, dairy will not increase your phlegm production. Though many people think otherwise, a study published in the American Review of Respiratory Disease found that drinking milk does not increase mucus production.5

The Phlegm-Dairy Connection

Did you know that the body produces about a liter of mucus a day?

Talk about being snotty.

Yellow

One possible sign of a viral or sinus infection.

One possible sign of a viral or sinus infection.

If you have yellow snot, it can mean that you have a virus or a sinus infection and that your body is fighting something off. The color is produced by a type of white blood cell that responds to infections and inflammations.1 When the white blood cells die, they burst, releasing a green pigment. The green pigment mixes with the mucus, giving it the yellow color. The color is usually brighter at first, possibly even appearing neon yellow. It typically darkens over a few days.

Staphylococcus aureus bacteria typically produce a golden-yellow mucus. Dark yellow phlegm could mean bronchitis or another type of infection in the chest.

If it's yellow, that does not necessarily mean that you need to go to the doctor. It just means your body is fighting against something. Remember, as of yet, there is no cure for the common cold, and antibiotics will only clear up bacterial infections. Viral infections just have to run their course. The best cure is your body’s own defenses.

See a doctor if the symptoms worsen or last longer than a week. You should also see a doctor you have a fever, headache, or a phlegmy cough for more than a few days.

Green

It is caused when white blood cells respond to infections and inflammations.

It is caused when white blood cells respond to infections and inflammations.

Green snot is actually just caused by a thicker concentration of the white blood cells that cause yellow snot. The color is usually brighter at first and darkens over a few days. Though conventional wisdom holds that yellow snot means virus and green snot means a bacterial infection, there is actually no scientific evidence to prove this.

Most doctors, in fact, don't even use mucus color as a reliable tool of diagnosis. Both green and yellow snot can result from viral infections. According to Dr. Matthew Rank, the color of snot is actually more of an indication of the length of symptoms if anything.5

A bacterial infection can result from a virus, however. When your sinuses become inflamed, they swell. This causes mucus to become trapped in your nasal passages. Over time bacteria and fungi can begin to grow in your sinuses, in which case you might need antibiotics.

If the symptoms have lasted more than 12 days or seem to be getting worse, see a doctor, especially if you are experiencing fever, cough with sputum, headache, and sinus pressure.2

Blue

Caused by Pseudomonas pyocyanea, also known as Pseudomonas aeruginosa.

Caused by Pseudomonas pyocyanea, also known as Pseudomonas aeruginosa.

Mucus can turn blue because of a certain bacteria called Pseudomonas pyocyanea, also known as Pseudomonas aeruginosa. It's fairly rare—about one in 10,000 stuffed-up people will have blue snot. If it changes to a thick blue color that lasts several days, you should see a doctor.

Blue can also happen if you have inhaled blue powder or something else blue in the air or because of some other contaminant. If this is the case, it should clear up within a day or two.

Did you know that you can have different colored mucus in each nostril?

There could be an infection or sore in one side that is not in the other. Now that's a nose of a different color.

Orange/Red/Reddish-Brown

Orange, red, or brown can be a sign of blood.

Orange, red, or brown can be a sign of blood.

If your mucus is tinged red or reddish brown, it is usually a sign of blood.2 The presence of blood is not necessarily a cause for alarm. The blood can come from a variety of causes. For example:

  • When the sinuses become inflamed, they can begin to bleed.
  • Frequent nose-blowing can cause sores to form at the base of the nose. Taking care to blow and wipe the nose gently can prevent this.
  • The tiny blood vessels in the nasal passages break easily, causing blood-tinged mucus. This can happen if the air is too dry, in which case using a saline spray to moisten the nasal passages will help.
  • Picking or rubbing your nose can also cause your snot to have a little blood in it.
  • If you are coughing up red or brown phlegm, it could be a sign of bronchitis.
  • Smoking can also irritate nasal passages, leading to slight bleeding. This, combined with tiny tobacco particles, will turn it a reddish-brown.

While a little bit of blood in your snot is not a problem, if you're blowing out large volumes of it, you should see a doctor.1

If there is a significant amount of blood that has lasted several days, you should see a doctor to determine the cause of the blood and whether treatment is necessary.

Brown

Brown mucus usually stems from smoking.

Brown mucus usually stems from smoking.

Brown or brownish-red snot is typically associated with smokers. It is mixed with particles from the cigarettes. Smoking can also irritate nasal passages, leading to slight bleeding. Smoking can also cause people to cough up the brown/red phlegm rather than just blowing it out of their noses.

The way to ease the production of brown phlegm is to smoke less.

Inhaling dust and dirt, while often leading to gray or black mucus, sometimes can also give it a brown tinge.

Black or Gray

May be a sign of air pollution.

May be a sign of air pollution.

Dark-colored mucus generally happens from inhaling pollutants in the air. The job of the mucus is to trap dirt or other particles and prevent them from getting further into the body. If there is ash, dirt, dust, smoke, or similar substances in the air, your nose will trap it.

Did you know that you could have purple, pink, or even blue snot?

Mixing up a pitcher of Kool-Aid can turn your snot the color of the drink if you accidentally breathe in a bit of the powder. Be careful not to breathe in powders, though. Those tiny particles are meant to go in your drink, not in your lungs!

If you find yourself coughing every time you lie down, it may be a sign of acid reflux.

If you find yourself coughing every time you lie down, it may be a sign of acid reflux.

How to Ease Cold Symptoms

Typically, a virus begins by producing an abundance of clear mucus, which turns a bright yellow or greenish color, then darkens over a period of a few days, usually turning somewhat green. At the end of the virus, it may turn a brown/red color. It should then start clearing up, becoming less thick until it returns to normal.

Ways to ease your symptoms:

  • Use nasal sprays, such as saline sprays, to keep the passages moist.
  • Drink plenty of fluids to thin the mucus and keep your upper respiratory system moist.
  • Don't starve a cold. Eating nutritious meals when you're sick is important. Your body needs the energy to fight off the bug.
  • Ease fever and body aches with Tylenol.
  • Reduce swelling and any inflammation with Ibuprofen.
  • Steam and hot liquids can help ease congestion.
  • Take Mucinex or another decongestant to loosen the phlegm and make coughs more productive.
  • Suck on cough drops to keep the throat moist. A spoonful of honey also can help alleviate the cough.
  • Take antihistamines to help alleviate the symptoms of a cough if it is caused by allergies.
  • See a doctor if you develop a fever that lasts for more than two days
  • Avoid smoking and second-hand smoke.

Remember, strange-colored mucus doesn't always mean there is a problem. You should only be worried if it persists for over 12 days, especially when other symptoms such as fever, headache, and cough are present.

Of course, these colors are just an indication of what could be wrong, not a precise diagnosis. You can still have an infection even with clear mucus. If you are concerned about something with your body, see a doctor.

How to Ease Cold Symptoms

How Much Do You Know About Snot?

For each question, choose the best answer. The answer key is below.

  1. What color mucus indicates an infection?
    • Clear/white
    • Green/yellow
    • Red/brown
  2. How much mucus does the average body produce a day?
    • 1 teaspoon
    • 4 gallons
    • 1 litre
  3. What is sputum?
    • A satellite built by the Russians
    • A mucus/saliva mix
    • The mucus that drips down the nasal cavity
  4. What does black mucus usually mean?
    • Pollutants in the air
    • Spoiled milk has been ingested
    • A virus
  5. What is mucus made of?
    • Gelatin
    • Mucinex
    • Water, cells, salts, and mucin

Answer Key

  1. Green/yellow
  2. 1 litre
  3. A mucus/saliva mix
  4. Pollutants in the air
  5. Water, cells, salts, and mucin

Sources

  1. Shmerling, Robert H, MD. "Don't Judge Your Snot By Its Color." February 8, 2016. Harvard Health Publications. Accessed April 3, 2017.
  2. Watson, Stephanie. Reviewed by Luqman Seidu, MD. "The Truth About Mucus." April 10, 2014. WebMD. Accessed April 3, 2017.
  3. Reviewed by Raj Sindwani, MD. "What the Color of Your Snot Really Means (Infographic.)" November 28, 2014. Cleveland Clinic. Accessed April 3, 2017.
  4. "Milk Products and Mucus in COPD." (n.d.) COPD Foundation. Accessed April 3, 2017.
  5. Pinnock, Graham, Mylvaganam, and Douglas. "Relationship between milk intake and mucus production in adult volunteers challenged with rhinovirus-2." Feb 1, 1990. American Review of Respiratory Diseases. Accessed April 3, 2017.
  6. Nierenberg, Cari. "You Think It's Mucus, but It's Not." December 10, 2008. ABC News. Accessed April 3, 2017.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

What Is and What 'Snot?

Mel on September 23, 2018:

Actually, I.came to this article because I have blue snot & I don't inhale anything through my nose excspt the air. I haven't been feeling very well. I've had multiple symptoms. I almost passed out the other day. I know what it's like to pass out too. I felt as though I was going to. I got my bearings though.

Paraic on May 29, 2017:

I'm waking every morning with blood and brown snot on my pillow dry snot and blood in my nose very sore head should I be concerned going on months now

King regards

Paraic

Been sick for 16 days already... on April 22, 2017:

Nose:

-liquidy snot is bright yellow

-thicker snot/boogers are bright green

The stuff I'm coughing up all the time:

Light yellow

riley on February 26, 2017:

I have been coughing up solid red yellow, and white mucus from a big bump in my nasal cavity. Any ideas.

Bonnita Claus on January 04, 2017:

In the morning, most days, I have 1 pr 2 clearing of my nose. It is usually very thick pale yellow with some green and often with a very thing thread of blood. It seems to be mostly rubbery. I seldom have to blow my noise the rest of the day, but when in the bathroom or working in kitchen my nose runs with a clear water. I assume a combination of activity and higher humidity brings this about. I have a theory that in the morning I am clearing out what my victims immune system, indicating I am healthy.

Am I right in thinking so? And have nothing to worry about. All my systems are go... note: 2 years ago I moved, improved my diet, now I no longer live in a state of stress, I have not taken antibiotics now since my last Cold that turned into a sinus infection about 2-1/2 yrs ago. I had one cold this year, lasted about 2-1/2 weeks, never developed a secondary infection, I refused to take antibiotics, waited to see if I developed and infection. My doctor wanted me to take preventive action with Antibiotics. I believe I did right for me.

mbroome on November 20, 2016:

Did a z pack for a cold 2 weeks ago blowing long strings looking light yellow occasionally is this normal. No fever

Unins000.exe on October 08, 2016:

Mine is bright purple . . .

Hurt all over on July 30, 2016:

Yellow/thick headace,pain in chest and back can't lay down without feeling like I'm drowning, took Mucinex DM also Robitussin DM only got worse now hurts to breathe or cough

roob on March 26, 2016:

That is SNOT true. Lol just kidding.

Ced Yong from Asia on March 16, 2016:

Okay, this is yeeky. But I can see that the yeekier it gets, the more attention you need to pay attention to it. :I

Sandi Kroeger from Minnesota, USA on March 02, 2016:

I have to say that, even after more than 30 years as a registered nurse, I have never seen anyone with blue snot...but reading about all the colors of snot made for a great hub. Thanks

aaditirani on February 11, 2016:

grate post i have ever read in this month thanking you for the useful information

IrateOrator on February 09, 2016:

This article completely grossed me out, but it is very informative and has me considering cutting back from smoking cigarettes

Mary from From the land of Chocolate Chips,and all other things sweet. on February 07, 2016:

Great informative hub, I didn't know people could actually have blue snot.

John R Wilsdon from Superior, Arizona USA on February 06, 2016:

This was an extremely extensive hub on the subject of snot. It is a great read during cold season, snot*hing could beat it. I vote this up despite the attempt at humor. Good job.

StyleinCraft on January 31, 2016:

Amazing..!!

StyleinCraft on January 21, 2016:

Thanks for sharing this information.

Melissa on January 16, 2016:

Hello

I have yellow sometimes green snot. It's been very dry out and cold and I'm wondering if that is causing this? When I use the nasal sprays it's yellow a couple times when I blow my nose then turns clear. I don't have any headaches or fever . Do I have a cold or infection ? Or is just dry ?

StyleinCraft on January 12, 2016:

I’ve done lots of research on blogging and your suggestions are amazing, clear, simple and thorough.

StyleinCraft on January 12, 2016:

Very Interesting. I also wish I knew how to implement some of this complex Features.

Maurice Glaude from Mobile on January 04, 2016:

I feel much better but I'm still dealing with Chest congestion. I don't normally get sick and haven't had a cold in over 3 years. Thanks for the refresher course on cold and mucus.

Amanda Holzinger from Pennsylvania on December 30, 2015:

Very informative! I shared this with my sister who has a 5 year old and she is alwaysn googling the colors of his mucus haha. voted up!

Ansel Pereira on October 16, 2015:

This has got to be one of the most detailed posts on varied aspects of mucous I have read in years. Well-researched and engaging in every sense. I used to develop dry mucous as a kid, not anymore. Great hub.

GreenMind Guides from USA on October 08, 2015:

Ew gross. But also wonderful. How did you manage both? Great hub.

Frank Quake on October 07, 2015:

I think this can be a good hub in person. I even have a girl World Health Organization has CF thus I've learned lots concerning secretion however such a large amount of individuals don't have any plan. i do know i used to be one amongst those individuals before Her designation and that i suppose this can be terribly helpful for everybody.

stella vadakin from 3460NW 50 St Bell, Fl32619 on October 02, 2015:

Hi , thought I would read your hub with cold season upon us. I really like the table chart you have included. Thanks, Stella

Venkatachari M from Hyderabad, India on October 02, 2015:

Very useful and important article for everyone.

Robert Morgan from Hutchinson Island, FL - Myrtle Beach, SC - Gilbert AZ on July 13, 2015:

Good article. Just finish all the antibiotics because Now, I a bloody nose mixed with clear when I blow my nose. Going back to see a Naturopath this time.

Aladdins Cave from Melbourne, Australia on June 27, 2015:

Great Hub, full of good information, BAR one !

I strongly recommend people STOP smoking, not reduce it.

Gave you thumbs up

Cheers from DOWNUNDER

Monique from Wichita, Ks on June 07, 2015:

I think this is a great hub personally. I have a daughter who has CF so I've learned a lot about mucus but so many people have no idea. I know I was one of those people before Her diagnosis and I think this is very useful for everyone.

Kristen Howe from Northeast Ohio on June 04, 2015:

Congrats on HOTD and the tons of comments here, especially since it's very useful, when it's cold and flu season, or due from allergies. Great job with informing us on mucus colors and their causes. Voted up!

Misha on June 03, 2015:

two days ago iwas a lil disoriented then i left work and instantly felt like i had a sore throat, the was fine for w few hours then i went into shakes and sweats and tried to sleep with no luck lol.... had to pee alot and had extreme fatigue in my bones and body.

i took some benilyn and my throat felt a slight bit better but nothing else really...then i started sneezing and it doesnt feel or sound like my normal sneewze its itchier and more squeeky than normal idk whyi think this but i do it doesnt feel like a normal sneeze... anyways my mucus is chunky whit/yellow and it has slightly bloody patched nothing over the top or anythiing but it has beentwo days now of like me sneezing a glob half way across the room of this gross stuff...i do have pets which i have slight allergy to so i assume they are making my nasal passage more irritated but i just wanted to make sure its not too serius

Terry Hoover from Denham Springs, Louisiana on May 15, 2015:

I had no idea that snot and boogers were so interesting! Nice work here on this unusual topic. Keep up the great writing. Voted useful.

Colin Garrow from Inverbervie, Scotland on April 21, 2015:

Who'd have thought snot could be so interesting! Great Hub.

regular teen on April 13, 2015:

im 13 and i have brown mucus come out but i don't smoke

Lloyd Benitez De Guzman from Puerto Princesa City, Puerto Princesa, Philippines on April 12, 2015:

A very informative article. Nice!

Krzysztof Willman from Parlin, New Jersey on April 10, 2015:

Wonderfully written and thoroughly explained. It may be "gross" to some but that's just a part of life and you want to make sure that you're always healthy and kickin'. Great informative hub. Voted up.

Sally Gulbrandsen from Norfolk on February 21, 2015:

Beautifully written article about a not so beautiful subject. Very informative, thank you very much for posting.

Ammon Beardmore on February 13, 2015:

This is gross yet extremely helpful! Thanks for posting.

SUNSHYNE from California, US on February 13, 2015:

Very informative hub. I just went to the doctor today and he told me I have severe allergies. Uggh. Everything is blooming early this year and that doesn't help one bit, or the fact that every person that walks in front of me lately seems to be a smoker. lol. (and if I had blue snot I would FREAK OUT) Thanks for the hub!

IrisMcdonald on February 11, 2015:

I really appreciate this article and will be passing the very clear very informative information on to friends. I think it gives people simple guides to reassurance and confidence to trust their own judgement .

Jodie on February 10, 2015:

Excellent and informative article :)

wingedshadowwolf on January 31, 2015:

Found this site because my snot has the bright yellow color of a highlighter marker! I'm just getting over a cold so this must be it hanging on, or a secondary infection. I've had some really green/yellow snot before but this was a new color to me!

Oscar Jones from Monroeville, Alabama on January 23, 2015:

I have previously experienced acute sinus infection that turned into viral pneumonia that put me out for thirty days. it started I believe it was triggered by sanding, using sheetrock mud and the mixture, I was snotting up white pasty phlegm but when the sinuses got to draining, I was bigtime dehydrating and then all colors and then solid black/ lung phlegm, but you can argue it was still sinus infection drainage, I could not hold my head up,serious headaches put me down, and put me out of consciousness. , could not stay hydrated, oh what a royal mess. well at the end of it and after air vaced to hospital 400 miles away, and thirty days I will never remember, doctors mixed up something one last time to try to save me, it was something like septra-antibiotic, while under almost total oxygen.. end of story, I am well today.. I am thankful. I will say this, A doctors recommendation is that you ask for real Sudafed from behind the counter with decongestant,. that the new aids outside on the shelves are not effective. pheneffreline is not able to do what the old Sudafed meds can do. --

The Schreibfeder on January 23, 2015: